Hery is a boy with strong practical abilities. Nowadays,he designed a LaunchPad which is not same as what you ever seen.
The LaunchPad is a touch screen divided into squares of N rows and M columns. Each square has two states of light and shade. And all squares are shady initially. When you touch the square in row X and column Y, the state of all the squares in the row and column will change. Now he wants to know how many squares are light on the LaunchPad after he makes multiple touches.

The first line of input contains two integers  denoting the rows and columns of LaunchPad.
The second line of input contains single integer  denoting the times of touch.
On the next Q lines,describe X and Y - the position of the square being touched. 

Print one line - the number of the squares that is on light state.

1 1
1
1 1

1

2 4
2
2 4
1 4

6